He added: "The presidency is bigger than any of us, so I have instructed my team to work as hard as they can to ensure it's a successful transition."

White House spokesman Josh Earnest insisted Obama would be sincere about ensuring a smooth handover when he meets Mr Trump, although he added: "I'm not saying it's going to be an easy meeting."

The talks will include the White House offering the Republican access to classified intelligence materials, including the president's daily brief.

It was a courtesy extended to Obama and his team by George W Bush.

The controversial tycoon is also expected to have a conversation with Prime Minister Theresa May "at the earliest opportunity" as the world waited on tenterhooks for signs of what a Trump presidency means for global politics.

Downing Street confirmed she was is preparing for a phone call with Trump as the "special relationship" between the UK and US begins a new chapter.

May was at pains not to endorse either Trump or his defeated Democratic rival Hillary Clinton during the bitter campaign, although she has previously described the president-elect's call to ban Muslims from entering the US "divisive, unhelpful and wrong."

Obama will give Trump access to classified documents and information to help the transition of power go smoothly

Britons will be keen for any indication of what Trump's victory, which sparked horror in some quarters of British politics.

The Republican regularly drew comparisons between Britain leaving the European Union and his campaign for the presidency, insisting his victory would be like "Brexit plus plus plus."

Although he has run a generally anti-global trade campaign, Mr Trump suggested in May that Britain would be favoured for any future trade deals, saying: "You'd certainly not be back of the queue, that I can tell you."

May on Wednesday wrote to Mr Trump to congratulate him on his victory, declaring that the UK and America will remain "strong and close partners on trade, security and defence."

It will be the billionaires first chance to check out his new home

The Republican has already spoken to the Israeli prime minister Benjamin Netanyahu, but the PM is likely to be near the front of the queue of other world leaders despite a potential realignment of America's global stance.

Many will be waiting to see the direction of Mr Trump's first conversation with Vladimir Putin, who he as repeatedly praised.

Hillary Clinton spoke for the first time on Thursday following her ballot box defeat

The Russian president has already sent Mr Trump a telegram of congratulation and expressed "his hope to work together for removing Russian-American relations from their crisis state".

After defying almost all pollsters' predictions, Mr Trump attempted reassure his opponents, promising to be a "president for all Americans" in a move that steadied financial markets.

Observers will also be looking for indications about the future in who he appoints to his cabinet and how he fills a vacancy in the Supreme Court.

Former New York mayor Rudy Giuliani, former House of Representatives speaker Newt Gingrich, and New Jersey governor Chris Christie are among those tipped for senior posts.